The third and final season of "The Leftovers" kicked off on April 16 with a cold open, showing a mysterious cult of people (who were based on a real religious sect called Millerism). From there, the show killed off two of its main characters within minutes and jumped forward in time three years.

As we learned more about how Kevin Garvey and the rest of Jarden's residents are doing, you might have missed some of the smaller moments that relate back to past plots and future themes.

Keep reading for a look at the six most important details you might have missed.

The woman we followed in the cold open was meant to represent a real religious sect called Millerites.

The people showing in the opening were inspired by Millerites.
HBO

INSIDER spoke with executive producer and the director for this episode, Mimi Leder, who revealed that the family we saw in the cold open were meant to be Millerites.

Millerism is a religious sect that began in the 1840s in New York. A farmer named William Miller came up with a new way to interpret the Book of Revelation, and did mathematical calculations to determine when the Second Coming of Christ would occur and worthy believers would be carried into heaven.

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There were a couple context clues that hinted at the people being Millerites. One was the series of dates shown on the chalkboard.

April 16 was the day this episode aired.
HBO

Miller's equations led to several predicted dates for the Second Coming of Christ. His first were deemed wrong because he had miscounted years, but when the final predicted date (October 22, 1844) did not end with believers being taken to heaven, the Millerites called it the Great Disappointment.

In the show, we see three dates: January 21, April 16, and August 7, 1844. The second date, April 16, was likely a nod to the premiere date of the episode.

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The Great Disappointment was actually written on a chalkboard in "The Leftovers" scene.

This was the biggest hint that the woman was a Millerite.
HBO

When the woman returned to the church after her third night of waiting, there was a chalkboard in the background that had "great disappointment" and "ballocks" and "fool" written on it.

The bombing was foreshadowed back in season one.

Evie's death was shocking.
HBO

Before the time jump, we see that Evie Murphy and the rest of her Guilty Remnant group were killed by a bomb dropped on the visitor center by an airplane. Though we don't know who ordered this done, it's made clear that the attack was likely organized by ATFEC — the Bureau of Alcohol, Tobacco, Firearms, Explosives and Cults.

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Back in season one, a government agent told Kevin Garvey that ATFEC could "eliminate" the GR if he wanted them to.

Kevin Garvey was stunned by the offer.
HBO

Kevin spoke with ATFEC agent Sean Kilaney in episode five of season one, "Gladys," after a GR member was found murdered.

"We could just eliminate the infestation," Kilaney said. "I can have three vans full of armed agents there by the end of the week. They pay a visit to whatever compound these f---s call home, and they get you the results you're looking for."

Kevin seemed concerned that the ATFEC representative was not interested in solving the murder case. When he asked what would happen, Kilaney said: "What happens is, they go away. They're not your problem anymore."

Clearly, ATFEC intervened in Jarden, but we don't know who called them in.

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Michael was reading the Mapleton Gazette's news site when Kevin walked in.

The Mapleton Gazette was on Michael's laptop.
HBO

The headline says "Mapleton Rebuilds After Heroes Day Violence," which is likely a reference to the horrific Memorial Day plot the GR carried out at the end of season one. But it might be a new story about recent violence?

Either way, we're very curious to know what Michael was perusing the Mapleton Gazette for. Maybe he was filling in the details for that section of the Book of Kevin?

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The Book of Kevin was actually sitting on the desk next to Michael, and Kevin put his sunglasses on top of it.

Kevin put his sunglasses right on the book.
HBO

When Matt asks Michael if Kevin saw "it," you probably assumed he was talking about whatever was on the computer. But Matt was likely referring to the Book of Kevin — which was sitting in plain view on the desk.

Mimi Leder told INSIDER that the choice to have the Book of Kevin out in the open was an idea that spontaneously came up on set that day.

"We decided just to see if we notice it, and [Kevin] puts his sunglasses on it," Leder said. "And that just happened when we were filming — it was fun when we decided to do it. We work hard on those details, but that one just happened on set."

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Kevin's "suicide" ritual matches the way Dean tried to kill Patti in season one.

Is Kevin making daily visits to "the hotel"?
HBO

One of the most unexpected moments (among many) of the episode was when Kevin seemed to perform a ritual of duct taping a plastic dry cleaning bag around his head and breathe in deeply until ... well, we don't know. We're not sure if he actually kills himself and comes back to life, or if he simply rips the bag before it's too late. But either way, this routine mimics the way Dean attempted to kill Patti in season one, when he tied a bag over her head and sealed it shut with tape.

Kevin intervened, tearing the bag before Patti suffocated. That was the last time we saw Dean before this season three premiere. It seems poetic to see Kevin alluding to this moment in the same episode when Dean returns and then subsequently dies himself.